Cancer is a major cause of death worldwide, being the second-leading cause of death in developed countries and even the number one cause of death in e.g. Australia, Japan, Korea, Singapore and the male population of the UK and Spain. The number of people who develop cancer each year is increasing.
Currently, cancer therapy involves surgery or focuses on the functional or genetic changes associated with the transformation of cells into malignant cells. An ideal anti-cancer drug should selectively kill, or at least inhibit, rapidly proliferating cancerous cells, while leaving non-cancerous cells unaffected. Recent approaches include immunotherapy using antibodies directed to markers of selected types of cancer cells (e.g. US patent application 2005/0244417), the application of agonists to receptors that are expressed on certain types of cancer cells (US patent application 2006/0147456), the application of interferon-containing chitosan-lipid particles (US patent application 2005/0266093), as well as the application of a compound that acts as a cytotoxic agent for a certain type of prostate cancer cells by an unknown mechanism (US patent application 2005/0245559).
A further approach on which research efforts have recently been undertaken is the development of an epigenetic cancer therapy, since abnormal patterns of DNA methylation in cancer cells are known for more than 20 years (for an overview see e.g. Brown, R. and Strathdee, G., Trends in Molecular Medicine (2002) 8, 4 (Suppl.), S43-S48, or Yoo, C. B. and Jones, P. A., Nature Reviews Drug Discovery (2006) 5, 1, 37-50). Nevertheless only two DNA methyl-transferase inhibitors, 5-azacytidine (Vidaza®) and decitabine (Dacogen®) have made it to the market. They have been approved for the treatment of myelodysplastic syndrome, a haematological condition also known as “preleukemia”. There is therefore still a need in the art for novel compounds and compositions for treating or preventing cancer or neoplastic disease that preferentially rapidly kill cancerous cells.
Accordingly it is an object of the present invention to provide a method, as well as compounds and compositions that are capable of preferentially killing a cancer cell without affecting a non-cancerous cell. It is a further object of the invention to provide a method of diagnosing the risk of tumourigenesis.